Side-by-Side Comparison Tables
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Four paired comparison tables, gathering related lakes from across this entire book into one place so you can drill a whole theme in one glance rather than flipping between sections.
Table 1 — World's "Big Four" superlatives vs. India's "Big Four" equivalents.
| Superlative | World holder | India's regional equivalent |
|---|---|---|
| Largest lake overall | Caspian Sea (saline) | Wular Lake (freshwater) — India has no true saline "largest overall" at world scale |
| Deepest lake | Lake Baikal | Manasbal Lake (deepest within Kashmir Valley only — a purely regional, not national, superlative) |
| Largest brackish lagoon | (No single dominant world answer; New Caledonia's lagoon is often cited as largest overall) | Chilika Lake (Asia's largest) |
| Most dramatically shrunk saline lake | Aral Sea | Sambhar Lake has not shrunk comparably — India has no domestic equivalent to this specific crisis |
| Largest reservoir | Lake Volta (by area) / Lake Nasser (among the largest by volume) | Govind Ballabh Pant Sagar/Rihand (by area) / Indira Sagar (by capacity) |
Table 2 — Four shrinking saline lakes, cause and status compared.
| Lake | Primary cause | Approx. scale of loss | Restoration status |
|---|---|---|---|
| Aral Sea | Soviet-era irrigation diversion of the Amu Darya/Syr Darya | Over 90% of volume | Partial recovery in the North Aral only, via the Kok-Aral Dam (2005) |
| Lake Chad | Reduced rainfall + irrigation withdrawal + rising evaporation, across four countries | Over 90% since the 1960s | No comparable dam-based recovery; security/humanitarian crisis layered on top |
| Lake Poopó | Mining/agricultural diversion + drought + evaporation | Effectively dried up entirely (2015) | No significant restoration to date |
| Lake Urmia | Upstream damming + agricultural withdrawal + reduced precipitation | Over 80–90% of historic volume | Partial recovery under an Iranian government restoration programme (2010s onward) |
Table 3 — Hazardous or unusual-chemistry lakes compared.
| Lake | Hazard/unusual feature | Location | Status |
|---|---|---|---|
| Lake Kivu | Limnic (gas) eruption risk | Rwanda/DR Congo | Actively, commercially degassed to reduce risk |
| Lake Nyos | Limnic eruption (historical disaster, 1986, roughly 1,700 deaths) | Cameroon | Fitted with degassing pipes after the disaster |
| Lake Monoun | Limnic eruption (smaller historical disaster, 1984) | Cameroon | Also degassed since |
| Lonar Lake | Occasional pink colour (halophilic algae bloom) | Maharashtra, India | Not hazardous — a chemistry curiosity, not a disaster risk |
| Lake Hillier | Permanent pink colour (algae and bacteria) | Western Australia | Not hazardous — a stable, benign curiosity |
| Lake Retba (Lac Rose) | Permanent pink colour (salt-tolerant algae), plus an active salt-harvesting economy | Senegal | Not hazardous — inhabited and economically active, unlike Hillier |
Table 4 — GLOF-relevant vs. non-GLOF Himalayan lakes.
| Lake | GLOF-relevant? | Note |
|---|---|---|
| South Lhonak Lake | Yes | Site of the October 2023 GLOF that damaged the Teesta-III dam |
| Nanda Devi glacial sources (Chamoli, 2021) | Yes (an ice-rock avalanche behaving like a GLOF) | Destroyed the Rishiganga project, damaged Tapovan-Vishnugad |
| Gangabal/Nundkol, Vishansar/Krishansar | Glacial origin, but no major recorded GLOF event | Popular trekking lakes, not currently flagged as high-risk |
| Roopkund | Glacial origin, but no GLOF association | Famous instead for its skeletons |
| Chandratal | Glacial/Ramsar, monitored as part of general Himachal glacial-lake tracking | No major GLOF recorded to date |
Memory hook: "Four tables, four running comparisons: world-vs-India superlatives, four shrinking-lake causes, five hazard/chemistry lakes, and which Himalayan glacial lakes have actually GLOF'd versus which are 'merely' glacial in origin."
Practice Recall: Before reading on, using Table 2 alone, state from memory the primary cause of decline for all four shrinking saline lakes without looking back.
Answer: Aral Sea (Soviet irrigation diversion), Lake Chad (rainfall decline + irrigation + evaporation across four countries), Lake Poopó (mining/agriculture + drought + evaporation), Lake Urmia (upstream damming + agricultural withdrawal + reduced precipitation).